Mixed modulus of smoothness and best approximation in Lorentz spaces

2025/09/26 by Akishev, G.
#41A25 #42A05 #Classical Analysis and ODEs (math.CA) #FOS: Mathematics

paper · doi:10.48550/arxiv.2509.22210

Abstract

The article deals with the mixed modulus of smoothness of positive order and the best approximation by ''angle'' of functions from the Lorentz space L_{p, τ}(\mathbbT^m). The properties of the mixed modulus of smoothness, the sharp version of the inverse theorem of approximation theory are proved.

Citations

• Marcinkiewicz-Zygmund inequalities in quasi-Banach function spaces
• Hardy-Littlewood and Ulyanov inequalities

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